Threonine: Food Sources & Daily Intake

Threonine is an essential amino acid — the body cannot make it, so it has to come from food. It is a structural building block of collagen and elastin (the proteins that give skin, tendons and cartilage their strength), and it is unusually concentrated in mucin, the slippery glycoprotein that forms the protective mucus layer lining the gut. Threonine is also needed to build antibodies (immunoglobulins) for the immune system. The richest dietary sources are lean animal proteins — meat, fish, poultry, eggs and cheese — followed by legumes, seeds and peanuts. The table below shows grams of threonine per 100 g of food; there is no FDA Daily Value for individual amino acids, so amounts are absolute.

Table of Contents

1. How to Read These Tables
2. Recommended Intakes & Upper Limits
3. Bioavailability & Absorption
4. Cooking & Storage
5. Vegetarian & Vegan Sources
6. Who Needs to Pay Attention
7. Data Sources & References
8. Connections
9. Featured Videos

How to Read These Tables

• Essential amino acid. Your body cannot synthesize threonine, so a regular dietary supply matters. The nine essential amino acids must come from food; the other eleven the body can build itself.
• Grams per 100 g, not %DV. There is no FDA Daily Value for individual amino acids, so this table reports the absolute grams per 100 g of food and ranks foods by that. A typical serving is shown beside each food.
• Complete vs incomplete protein. Animal foods are “complete” — they carry all the essential amino acids in good proportion. Most single plant foods are lower in one or two; eating a variety of legumes, grains, nuts and seeds across the day covers the gaps.

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Recommended Intakes & Upper Limits

Your personal target depends on age, sex and pregnancy. The Daily Value used for the %DV column above is a single label figure; the table below is the age-specific guidance.

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Bioavailability & Absorption

Threonine from food is well absorbed as part of dietary protein. What matters most is total protein quality and quantity: animal proteins (meat, fish, eggs, dairy) are complete and threonine-rich, while plant proteins are usually a little lower in threonine and benefit from variety. A notable share of dietary threonine is taken up by the gut itself to build mucin, so a steady supply from everyday meals helps keep the intestinal lining well maintained.

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Cooking & Storage

Amino acids are stable to ordinary cooking — threonine is not destroyed by normal heat, and cooking actually makes protein easier to digest. Very high, prolonged dry heat (charring) plus sugars can tie up some amino acids through browning reactions, but everyday cooking leaves threonine intact. No special handling is needed.

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Vegetarian & Vegan Sources

Plant-based eaters can get plenty of threonine, but it takes a little planning because plant proteins are less threonine-dense than animal ones. The strongest plant sources are lentils, white and black beans, chickpeas, peanuts, pumpkin and sesame seeds. Combining legumes with grains across the day (for example beans with rice, or lentils with bread) supplies all the essential amino acids; total protein simply needs to be a bit higher than for omnivores to reach the same threonine.

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Who Needs to Pay Attention

Outright threonine deficiency is rare in anyone eating enough total protein. The groups who should pay attention are those with low overall protein intake — some older adults (who need more protein per kilogram to maintain tissue), people recovering from illness, surgery or wounds (when collagen-rich repair raises demand), and very-low-calorie dieters. Because threonine is heavily used to build the gut’s mucin barrier, a chronically low-protein diet can also leave that lining under-supplied. The fix is simply adequate quality protein, not isolated threonine supplements.

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Data Sources & References

• NIH MedlinePlus — Amino acids
• Linus Pauling Institute — protein and essential amino acids
• PubMed — threonine, mucin and intestinal barrier
• PubMed — threonine requirement of healthy adults

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Connections

• Threonine (Main Page)
• Threonine Benefits
• Threonine History
• All Amino_Acids
• Lysine
• Methionine
• Glycine
• Bone Broth

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